Studies reporting prevalence rates of substance use often rely on self-report to do so. This is a serious limitation given the problem of underreporting, especially among certain subgroups. Underreporting of drug use is particularly prevalent among pregnant women due to increased social stigma and fear of negative consequences (such as arrest or loss of child custody). Thus, prenatal drug use often goes undetected, and an ideal opportunity for intervention and potential prevention of adverse maternal and infant outcomes is being missed. To address issues of underreporting, Drs. Ondersma and Svikis (mentors for this proposal), through a NIDA-funded R21, are developing and validating an indirect measure designed to identify problem drug use in post-partum women without requiring self-report of such use. Given the unique circumstances of pregnancy and increased stigmatization of prenatal drug use, it is likely that the indirect items which predict drug use in pregnant women might differ from those found for post-partum women. The current project proposes to adapt the research methods developed by Ondersma and Svikis in order to test and validate an indirect measure of drug use in a sample of pregnant women. This will be accomplished in a two part study involving women attending their first prenatal care visit at the Women's OB/Gyn Clinic, part of the VCU Health System. Study 1 will involve administration of the Wayne Indirect Drug Use Screener (WIDUS) adapted for use with pregnant women, and testing of urine samples from 150 pregnant women. Data analysis will then identify items associated with prenatal drug use by comparing questionnaire response data to urine drug assay findings. Study 2 will cross validate the newly-developed indirect measure in a second sample of 75 pregnant women with the goal of achieving a specificity of .70 or greater and a sensitivity of .90 or greater. Finally, the final item content for the WIDUS for pregnant women will be compared to those identified through the Ondersma and Svikis study with postpartum women to determine if the same or different items best predict illicit drug use in the two groups of women. The development of an indirect measure of drug use for pregnant women would be of major clinical importance (allowing non-threatening intervention with a targeted sample of at-risk women) as well as scientific importance (allowing exploration of methods for achieving greater population impact). PUBLIC HEALTH RELEVANCE: The purpose of this study is to develop and validate an indirect drug screening tool of pregnant women. Prenatal care providers could then use this tool to identify pregnant women at risk for drug use and provide them with education and intervention, thereby reducing risks for adverse maternal and infant outcomes.